1. Technical Field
The present disclosure generally relates to audio devices.
2. Description of Related Art
Audio devices, such as MP3 (MPEG-1 audio layer III) players, MP4 (MPEG-4) players, CD (compact disc) players, and so on, are widely used. An audio device reproduces audio signals, amplifies the audio signals by an amplifier, and outputs amplified audio signals by an internal sound producer such as speaker. An earphone jack is usually defined in the audio device, so that an external sound producer such as an earphone can be detachably connected to the audio device via the earphone jack to output the amplified audio signals.
The audio device further includes a controller to generate a control signal, which is used for controlling the amplifier to output the amplified audio signals to one of the internal speaker and the external earphone. When the external earphone is not connected to the audio device, the amplified audio signals are sent to the internal speaker. When the external earphone is connected to the audio device, the amplified audio signals are sent to the external earphone.
However, the control signal may be disturbed by the amplified audio signals especially when the amplified audio signals are outputted to the internal speaker. As a result, the audible sound outputted by the speaker may be intermittent and has a low sound quality. Therefore, an audio device with good sound quality is desired.
Other advantages and novel features will become more apparent from the following detailed description of an exemplary embodiment when taken in conjunction with the accompanying drawings.